Remifentanil for General Anesthesia in Preeclamptics
Nyckelord
Abstrakt
Beskrivning
General anesthesia for cesarean section involves rapid sequence induction with a muscle relaxant and barbiturate followed by endotracheal intubation. Although the use of opioids may blunt haemodynamic responses to endotracheal intubation, they are avoided in pregnant patients due to possible respiratory depressants effects on neonates.Preeclamptic patients response with exaggerated sympathoadrenal reflex to anesthesia induction and intubation. The resulting hypertension and tachycardia may result in cerebrovascular accident, pulmonary edema, arrhythmias, increased myocardial oxygen consumption and fetal hypoxia by uterine vasoconstriction. Several drugs have been used to blunt the hemodynamic disturbances to intubation, but none of them have been implicated for routine use for general anesthesia in preeclamptic patients.
Recently remifentanil has started to be used in general anesthesia of high risk obstetric patients. Remifentanil is a μ-opioid receptor agonist that is metabolized by nonspecific blood and tissue esterase hydrolysis. It has a low distribution volume with a context sensitive half life of 3 minutes. Its elimination half life is 12 minutes even after repeated boli. Previously remifentanil use in pregnant patients with cardiac pathology has been reported with minimal neonatal side effects. A randomized controlled study in normal parturient has shown that remifentanil is transferred through placenta and may cause mild neonatal depression that is easily managed. Umbilical artery and vein remifentanil concentrations has shown that remifentanil is quickly redistributed or metabolized in fetus. Thus, remifentanil may be an appropriate drug for induction and maintenance of general anesthesia in severe preeclamptic patients.
Datum
| Senast verifierad: | 11/30/2007 |
| Först skickat: | 12/03/2007 |
| Beräknad anmälan inlämnad: | 12/03/2007 |
| Först publicerad: | 12/04/2007 |
| Senaste uppdatering skickad: | 12/03/2007 |
| Senaste uppdatering publicerad: | 12/04/2007 |
| Faktiskt startdatum för studien: | 01/31/2008 |
| Beräknat slutfört datum: | 11/30/2009 |
Tillstånd eller sjukdom
Intervention / behandling
Drug: R
Drug: C
Fas
Armgrupper
| Ärm | Intervention / behandling |
|---|---|
| Placebo Comparator: C Saline starting before induction till entry to abdominal cavity | Drug: C same volume iv bolus before induction followed by same volume infusion |
| Active Comparator: R Remifentanil starting before induction till entry to abdominal cavity | Drug: R 1 microg/kg iv bolus before induction followed by 0.5 microg/kg/min infusion |
Urvalskriterier
| Åldrar berättigade till studier | 18 Years Till 18 Years |
| Kön som är berättigade till studier | Female |
| Accepterar friska volontärer | Ja |
| Kriterier | Inclusion Criteria: - Severe preeclamptic parturients with single fetus pregnancy with contraindication to regional anesthesia Exclusion Criteria: - Known allergy to study drugs - Known fetal anomaly and /or gestation week and /or estimated to be nonviable (fetal weight <400 gr, gestational week<24 weeks) - Known cardiac disease diagnosed prior to pregnancy - Known drug abuse in the parturient - Multifetal gestation - Anticipated difficult airway management (mask ventilation and/or endotracheal intubation). |
Resultat
Primära resultatåtgärder
1. Blood pressure [Induction to post-intubation period]
Sekundära resultatåtgärder
1. Heart rate [Induction to delivery]
2. Amount of additional drugs and fluids if required [Induction to delivery]
3. Evaluation of the newborn [Within 10 min following delivery]
